Final Exam Chem
what is the oxidation number of hydrogen in KH?
-1
what is the oxidation number of hydrogen in compounds containing metals?
-1
What is the oxidation number of oxygen in most compounds?
-2
In a compound, the algebraic sum of the oxidation number of all atoms equals
0
what is the oxidation number of a pure element?
0
The molar mass of LiF is 25.95 g/mol. how many moles of LiF are present in 10.37 g
0.3998 mol
For the reaction represented by the equation Pb(NO3)2 + 2KI → PbI2 + 2KNO3, how many moles of lead(II) iodide are produced from 300. g of potassium iodide and an excess of Pb(NO3)2?
0.904 mol
which coefficients correctly balance the formula equation CaO + H₂O = Ca(OH)₂?
1,1,1
which coefficients correctly balance the formula equation NH₄NO₂(s) = N₂(g) + H₂O(l)?1,1,2
1,1,2
For the reaction represented by the equation Cl2 + 2KBr → 2KCl + Br2, how many moles of potassium chloride are produced from 119 g of potassium bromide?
1.00 mol
For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of sodium hydroxide are produced from 3.0 mol of sodium with an excess of water?
120 grams
what is the percentage composition of CF4
13.6% C, 86.4% F
What is the formula mass of (NH4)2SO4
132.16 amu
in the reaction represented by the equation N2+3H2-->2NH3 what is the mike ratio if hydrogen to ammonia
2:1
which equation is not balanced?
2H2 + O2 = H2O
Which reaction does not occur?
2HF(aq) + Cl2(g) -> F2(g) + 2HCl(aq)
If 0.500 mol of Na+ combines with 0.500 mol of Cl- to form NaCl, how many formula units of NaCl are present
3.01 x 10^23
how many OH- ions are present in 3.00 mol of Ca(OH)2
3.61 x 10^24
For the reaction represented by the equation 2Na + 2H2O → 2NaOH + H2, how many grams of hydrogen are produced if 120g of sodium and 80g water are availble
4.5
What is the mass of 0.240 mol glucose, C6H12O6?
43.2 g
what is the percentage composition of CuCl2
47.27% Cu, 52.73% Cl
In the reaction represented by the equation 2Al2O3 → 4Al + 3O2, what is the mole ratio of aluminum to oxygen?
4:3
For the reaction represented by the equation 2HNO3 + Mg(OH)2 → Mg(NO3)2 + 2H2O, how many grams of magnesium nitrate are produced from 8.00 mol of nitric acid, HNO3, and an excess of Mg(OH)2?
593 grams
how many Mg2+ ions are found in 1.00 mol of MgO
6.02 x 10^23
how many oxygen atoms are there in 0.500 mol of CO2
6.02 x 10^23
The molar mass of NH3 is 17.03 g/mol. how many moles NH3 are present in 107.1 g
6.289 mol
what is the mass percentage of chlorine in NaCl?
60.7%
For the reaction represented by the equation AgNO3 + NaCl → NaNO3 + AgCl, how many moles of silver chloride, AgCl, are produced from 7.0 mol of silver nitrate AgNO3?
7.0 mol
When the formula equation Fe3O4 + Al → Al2O3 + Fe is correctly balanced, the coefficient of Fe is
9
For the reaction represented by the equation N2 + 3H2 → 2NH3, how many moles of nitrogen are required to produce 18 mol of ammonia?
9.0 mol
how many molecules are there in 5.0 g of methyl alcohol, CH3OH
9.4 x 10^22
For the reaction represented by the equation SO3 + H2O →H2SO4, calculate the percentage yield if 500. g of sulfur trioxide react with excess water to produce 575 g of sulfuric acid
91.2%
What is the formula mass of magnesium chloride, MgCl2
95.21 amu
What is the name of a list of elements arranged according to the ease with which they undergo certain chemical reactions?
Activity series
The measured amount of a product obtained from a reaction
Actual yield
What is the formula for aluminum sulfate?
Al2(SO4)3
which of the following is a formula equation for the formation of carbon dioxide from carbon oxygen?
C + O2 = CO2
A compound's empirical formula is CH. If the formula mass is 26 amu, what is the molecular formula?
C2H2
A compound's empirical formula is CH3. If the formula mass is 30 amu, what is the molecular formula?
C2H6
A Compound contains 27.3g of C and 72.7g of O. What is the empirical formula?
CO2
The reaction of calcium oxide, CaO, with water yields
Calcium hydroxide
What is the study of the mass relationships of elements in compounds?
Composition Stoichiometry
The reaction represented by the equation 2HgO(s) -> 2Hg(l) + O2(g) is a(n)
Decomposition reaction
The reaction represented by the equation Pb(NO3)2(aq) + 2KI(aq) -> PbI2(s) + 2KNO3(aq) is a
Double-displacement reaction
what is the formula for hydrochloric acid?
HCl
Oxides of active metals, such as CaO, react with water to produce
Metal hydroxides
In the word equation, sodium oxide + water >> sodium hydroxide, the formula for sodium hydroxide is represented by
NaOH
Predict what happens when nickel is added to a solution of potassium chloride
No reaction occurs
What is the formula for the compound formed by lead (II) ions and chromate ions?
PbCrO4
When a slightly soluble solid compound is produced in a double-displacement reaction, a
Predicate is formed
what is the balanced equation for the combustion of sulfur?
S(s) + O2(g) = SO2(g)
What is the formula for sulfur dichloride?
SCl2
What is the formula for silicon dioxide?
SiO2
What can be predicted by using an activity series?
Whether a certain chemical reaction will occur
A molecular compound has the empirical formula XY3. Which of the following is a possible molecular formula?
X2Y6
The complete balanced equation for the reaction between zinc hydroxide and acetic acid is
Zn(OH)2 + 2CH3COOH Zn(CH3COO)2 + 2H2O
A chemical formula for a molecular compound represents the composition of
a molecule
What is the maximum possible amount of product obtained in a chemical reaction?
actual yield
In the equation 2Al(s) + 3Fe(NO3)2(aq) -> 3Fe(s) + 2Al(NO3)3(aq), iron has been replaced by
aluminum
Name the compound Al2S3
aluminum sulfide
An element in the activity series can replace any element
below it on the list
name the compound CCl4 using the stock system
carbon(IV) chloride
To balance a chemical equation, it may by necessary to adjust the...
coefficients
To balance a chemical equation, it may necessary to adjust the
coefficients
The reaction represented by the equation 2KClO3(s) -> 2KCl(s) + 3O2(g) is a(n)
decomposition
In what kind of reaction does a single compound produce two or more simpler substances?
decomposition reaction
Name the compound N2O3
dinitrogen trioxide
In what kind of reaction do the ions of two or compounds exchange places in aqueous solution to form to new compounds
double displacement reaction
the equation AX + BY = AY + BX is the general equation for
double-displacement reaction
a formula that shows the simplest whole number ration of the atoms in a compound is the
empirical formula
what is the sum of the atomic masses of all the atoms in a formula for a compound?
formula mass
A compound contains 64 grams of O and 8 grams of H. What is the empirical formula for this compound?
h20
The replacement of bromine by chlorine in a salt is an example of a single-displacement reaction by
halogens
Group 1 metals react with water to produce metal hydroxides and
hydrogen
Magnesium hydroxide decomposes to yield magnesium oxide and
hydrogen
Which word equation represents the reaction that produces water from hydrogen and oxygen?
hydrogen plus oxygen yields water
Name the compound Fe(NO3)2
iron (II) nitrate
In most chemical reactions the amount of product obtained is
less than the theoretical yield
which reactant controls the amount of product formed in a chemical reaction
limiting reactant
When heated, metallic chlorates decompose into
metallic chlorides and oxygen
in the chemical reaction represented by the equation wA +xB -->yC+zD a comparison if the number of moles of A to the number of moles of C would be an
mole ratio
a balanced chemical equation allows one to determine the
mole ratio of any two
Name the compound N2O2 using the stock system
nitrogen(II) oxide
A chemist interested in the efficiency of a chemical reaction would calculate the
percent yield
What is the ratio of the actual yield to the theoretical yield, multiplied by 100%
percentage yield
the coefficients in a chemical equation represent the
relative numbers of moles of reactants and products
An active metal and a halogen react to form a(n)
salt
A chemical equation is balanced when the
same number of each kind of atom appears in the reactants and in the products
The reaction represented by the equation Mg(s) + 2HCl(aq) -> H2(g) + MgCl2(aq) is a
single-displacement reaction
Which branch of chemistry deals with the mass of relationships of elements in compunds and the mass relationships among reactants and products in chemmical reactions?
stoichiometry
What is the small whole number that appears as a factor in front of a formula in a chemical reaction
subscript
Name the compound SO3
sulfur trioxide
in what kind of reaction do two or more substances combine to form a new compound?
synthesis reaction
the equation A + X = AX is the general reaction for a
synthesis reaction
If the percent yield is equal to 100 then
the actual yield is equal to the theoretical yield
in the chemical equation wA+xB-->yC + zD if one knows the mass of A and the molar masses of A B C D one can determine
the mass of any of the reactants or products
A chemical formula includes the symbols of the elements in the compound and subscripts that indicate
the number of atoms or ions of each element that are combined in the compound
to determine the limiting reactant in a chemical reaction involving known masses of A and B, one could first calculate
the number of moles of B and the number of moles of A available
the word equation solid carbon + oxygen gas --> carbon dioxide gas + energy represents a chemical reaction because...
the reaction releases energy
Some acids, such as carbonic acid, decompose to nonmetal oxides and
water
